Currency change ratio isn't right

Every time you sell something in the market, we will see that the amount of gold that the currency can buy.
For example, if i sold 100 tanks with a price of 30 cny, the total amount which is 3000 cny will show at the interface. At the same time, the amount of gold that 3000 cny can buy is also showed.
Here comes the problem, it shows me 6 gold. That means the gold2cny change ratio is 1:500, which is obviously not true. Even when I sold something in ESP, it also shows me that the ratio is 1:500.

What I want to say is, this function is fantastic, but the totally wrong ratio makes this function useless.